(a) Field of the Invention
The present invention relates to a high resolution lens system for micro film.
(b) Description of the Prior Art
Though light sources emitting visible rays have conventionally been used for photographing on micro films, it is now demanded to photograph reduced images with higher resolution. Examinations made to meet such a demend have indicated that it is possible to photograph reduced images with higher resolution by using a light source emitting rays of higher energy and a sensitive material assuring higher resolution. Speaking concretely, rays emitted from a mercury lamp contains a line of 3650 A which has very high energy. By using this line in combination with such a sensitive material as mentioned above, resolution can be enhanced up to 1.mu..
However, the above-mentioned line has a short wavelength, thereby restricting use of glass material having high refractive index which reduces transmittance. It is therefore very difficult to design a lens system having high resolution.